Transmission



May 16, 1944. A. 1.. JOHNSON TRANSMISSION Filed March 24, 1941 8 Sheets-Sheet l aw an IN V EN TOR. $56M 1 Johmum/ 8 Sheets-Sheet; 2

R m m ay 15, 1944. l A. L.'JOHNSON TRANSMISSION Filed March 24, 1941 A. L. JOHNSON TRANSMISSION Filed March 24, 1941 8 Sheets-Sheet 3 fl 66 mb BY a A ORNEYS.

May 16, 1944. A. :L. qbH soN TRANSMISSION Filed March 24. 1941' 8 Sheets-Sheet 4 INVENTOR. fl/fmtfl. Jofihumz BY RNEYS.

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A. L. JOHNSON TRANSMISSION Filed March 24, 1941.

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A. L. JOHNSON TRANSMISSION 8 Sheets-Sheet 8 Filed March 24, 1941 5mm? M W MM m Patented May 16, 1944 UNITED STATE TRANSMISSION Albert L. Johnson, wmte nesi- Lake, Mimn, assignor to Johnson Power-n Transmission Corporation, St. Paul, Minn., a corporation of Minnesota Application March 24, 1941, Serial No. 384,792

32 Claims.

' My invention relates to an improvement in transmissions wherein it is desired to provide a power transmitting device in'which the gears are constantly in mesh.

Transmissions of various types hav been previously constructed in which the gears are arranged in epicyclic trains, sothat all of the gears remain constantly in mesh. Various difllculties have arisen with these former constructions. In the first place, the bulkof the gears rotating with the drive or driven shaft has limited the number of speed changes of the driven shaft with relation to the driv'e shaft. In other words, the number of gear ratios which could be attained without too greatly increasing the weight of the rotating parts was thought to be greatly limited;

In the previously filed application for patent for automatic transmission, Serial No. 315,216, filed January 23, 1940, a transmission was illustrated in which a pair of ring gears were connected together, each of which meshed with a planetary gear. planetary gears travelled at a speed equal to, or greater than,.the speed of the drive shaft. One set of planetary gears comprised double gear means including a pair of different diameter gears integrally connected together. Each of the gears of "th double gear was provided with a sun gear, one of which was on the driven shaft, and the other of which was ordinarily rotatable with respect thereto. The planetar gear means connected to the other ring gear was also provided with a sun gear. By holding various combinations of the sun gears stationary, and by locking certainparts of the mechanism together, various speed ratios could be obtained.

I have found that, while the original construction illustrated in the application above referred to was practical, useful, and advantageous, it was poss ble to approximately double the speed 'Ifhe gear carriers for these from reverse to the highest. forward speed ratio, all of the gears are constantly in mesh.

It is a feature of my invention that my transmission may be controlled by operation of a pivoted lever which may merely pivot from one extreme position to the other. In one extreme position of the lever, the transmission is in reverse. Movement of the lever shifts the transmission through neutral position to forward speed positions, the speed ratio gradually increasing as the lever pivots to its other extreme V position. Such a control is of extreme advantage, particularly for tanks and tractors. If two to its wheel or tread providing no break in power ratios obtainable without appreciably increasing the working parts necessary. Accordingly, the

p esent invention relates to an lmproved construction wherein a great number of speed ratios can be obtained.

It is an object of the present invention to I provide a transmission which is so constructed during the shifting process and as any desired relation between the speeds of the wheels or treads may be instantly obtained without the use of brakes or other such means to mechanically hold one wheel or tread stationary, or to slacken the speed of the same.

. It is further 'a feature of my invention that my transmission is so. controlled that it may operate as an automatic transmission, or may be maintained in a predetermined speed ratio. If, for example, it is desired to prevent the vehicle bearing the transmission from going into overdrive while going down a hill or g ade, this may be accomplished. Thus-my transmission has all of the advantages of the usual automatic transmission without the usual difficulties attendant thereto.

These and other objects and novel features of my invention, will be more clearly and fully set forth in the following specification and claims.

In the drawings forming a part of my spec'- iflcation:

Figure l is a longitudinal sectional view through th transmission, showing the relationship of .the parts.

Figure 2 is an end .vlew of the brake band operating mechanism, the view being taken sec.-

tional through the transmission'housing on the line 2-4 of Figure 1.

Figure 3 is a cross-sectional view through the mechanism for connecting. certain of the sun ears to travel in unison in the transmission on the line 3- -3 of Figure 1.

Figure 4 is a cross-sectional viewthrough the transmission, the position of the section being indicated by the line 4-4 of Figure 1.

Figure 5 is a cross-sectional view through the transmission, the position of the section being indicated by the line 5-5 of Figure 1.

Figure 6 is a side elevation detail view of a clutch operating mechanism used in my transmission.

Figure 7 is a diagrammatic view of the manner in which the brake bands are actuated.

Figure 8 is a cross-sectional view through the control mechanism for the transmission, the position of the section being indicated by the line in unison.

Figure 13 is a-diagrammatic view of the operating mechanism of a tank or tractor, showing the manner in which the transmission may be positioned with relation thereto.

Figure 14 is an elevation view, partly in section, of a control valve for a tank or tractor of the type illustrated in Figure 8 of the drawings.

Figure 15 is a sectional view through the transmission, with the gears and shafts thereof omitted, illustrating an alternative method of holding stationary the brake drums connected to the various sun gears.

Figure 16 is an end view of the brake operating mechanism, the position of the section being indicated by the line "-48 of Figure 15.

Figure 17 is a diagrammatic view of an alternative arrangement of double ring gear and planetary gears.

Figure 18 is another diagrammatic view of an alternate arrangement of double ring gear and planetary "gears.

ure 19 is still another diagrammatic view of a modified form of ring gear arrangement.

Figure 20 is a sectional view through a slightly modified form of transmission, showing inter-- locking clutches of a somewhat different form from that previously disclosed.

Figure 21 is a perspective view of one of the clutch gears used in connecting certain of the rotating parts together.

In order that the invention be clearly understood, the transmission itseli', and the construction thereof, will first be explained. The control means for the transmission will be more readily understood once the structure of the transmission has been described.

The transmission is designated generally by the letter A, and includes a drive shaft III, which in the present case is an engine crank shaft, and an axially aligned driven shaft II. The drive shaft 10 is provided with an end flange I 2, to which is bolted by bolts II, the huh I of anend plate IS. The hub ll encircles the driven shaft II, and is placed therefrom by means of the bearing l6.

The end plate I5 is equipped with a cylindrishaped flange It extends outwardly from. the cylindrical flange l'l intermediate the ends of the flange IT. A gear ring 20 encircles the flange i'l on-one side of the flange I9, and the substantially cylindrical wall It of a housing 22 encirclesv the flange II on the other side of the flange i9. Bolts 23 extend through the flanged edge '14 of the housing 22, through the flange l8, and into the gear ring 20, holding the housing 22 and the gear ring 20 in proper relation to the supporting end plate It. The gear ring 20 is ordinarily engaged by a pinion on a starting motor, not shown.

Aswill be best seen in Figures 1 and 5 of the drawings, the outer race 25 of a one way clutch is secured within the flange II. Keys 20 (see Figure 5) hold this outer race 26 from rotation relative to the flange i1 and end plate l5. Balls or rollers 21 are positioned in wedge-shaped slots 20 in the outer race 25. Spring elements Ill may be positioned between the rollers 2'] and one end ii of the slots 29, to insure the engagement of the rollers 21 with the inner race of the one way clutch when the outer race is travelling as fast as the inner race. As the outer-race 2! is secured for rotation with the drive shaft, it will be seen that the inner race will travel as fast or faster than the outer race at all times, as it is prevented from travelling at a slower rate of speed by theme way clutch.

The hub ll is provided with an axial Bore-oi somewhat greater diameter than the outer diameter of the bearing I6 which it encircles: and a ring 31 substantially fills this axial bore. The ring 82 could be made a part of the hub H, but for ease of assembly is formed as a separate ring whichoverlies the bearing l8 and rotates with the hub ll. 4

A planet gear carrier 33 encircles the-bearing I adjacent the ring 32. This planet gear carrier ll is in the form of a disc having a substantially cylindrical ring I4 at its outer extremity. The ring 3| forms the inner race of the one way clutch previously described; and the rollers 21 engage the outer surface of this ring u when there is a tendency for the gear carrier 33 to travel at a slower rate of speed than the outer race 25 thereof. A circumferentially extending flange 8! extends outwardly from one edge of the ring 34 into overlapping relation with the flange I! to hold the rollers 21 in their proper place.

Under certain circumstances which will be later described'in detail, it is desirable to have the gear carrier move in unison with the drive shaft III. In order that this result may be attained, I provide a series of slidable pins in suitable recesses in the hub ll. The pins 30 are arranged with their axes parallel to the axis of the drive and driven shafts: and the pins it are angularly spaced about the axis of the hub. These pins ll are provided with tapered ends 3'! designed to fit into corresponding angularly spaced recesses 39 in the gear carrier I3. 'Ihe pins 36 extend through aligned apertures in the hub and in the ring 34. In one extreme position they are entirely withdrawn from engagement with the gear carrier 33, while in the other cal flange ll near the periphery thereof. A i'ing- 7 extreme position they engage into the gear carrier to hold the hub and gear carrier interlocked for rotation in unison.

The hub I4 is provided with radially extending slots 4| which extend outwardly from each pin receiving recess. Actuating pins 4| are posi-' bolts 51.

tioned in each of these slots 40 by means of which the pins 39 are moved longitudinally between the extreme positions described. The outer ends of the actuating pins '4I, extend through an axially slidable ring 42. Heads 43 on the pins 4| limit the inward insertion of the pins 4 I, and a retaining band 44 encircles the ring 42 and extends over the heads 43 to hold the actuating pins in place.

. The ring 42 is externally grooved at 45 to receive a relatively movable ring 45 by means of which the ring 42 may be moved axially of the hub l4. The ring 48 is pivotally connected to a.

slide yoke 41 in a manner not shown. but well known in the art. The slide yoke is pivoted at 46 causes movement of the ring 42; movement of the ring 42 causes movement of the actuating pins 4|; and movement of the actuating pins 4| causes longitudinal sliding of the pins 30 into which-the ends of the pins 4| engage.

Spaced from the gear carrier 33, and extending parallel thereto, I provide a second gear carrier disc 53. At angularly spaced intervals about the gear carrier 33, I provide project ng portions 54 which extend toward the carrier disc 53. These large bosses or projecting portions have apertures 55 therein to receive securing nuts 59 of securing The carrier disc-53 is provided with complementary bosses 59 which "contact the bosses 54. The securing bolts 51 are threadably movementof the ring 49; movement of the ring bosses 16 in the planet gear carrier 14 and nuts- 00 on the studs 19 hold the planet gear carrier 14 and 15 from relative rotation. The angular relationship of the bosses 16 and 11, and the gears carried by the gear carriers 14 and15 may be seen in Figure 4.

The planet gear carriers 14 and 15 support ball or roller bearings BI and 82, respectively, which support the stub shaft ends 83 and 84,, respectiveiy, of the double gear units 85. The double gear units '85 include a smaller diameter gear 86 and a larger diameter 91 which are integrally engaged in the bosses 59 of the gear carrier disc" 53. Thus, at angularly spacedpo nts. the gear carrier discs 33 and 53 contact one another, and

are secured in position by the bolts 51.

Needle bearings 60 are interposed between the gear carrier discs 33 and 53. units 5| are supported on the bearings 60. Fig- 120 apart. about the center of the transm ssi n.

Between the gear units 9|, the connecting bosses 54 may be seen substantially filling the space. The bosses 54 may be connected as shown in Figure 5, if desired.

The double gear units 5i include two gears 52 and 53 of-diilerent diameter. The gear 52 is positioned to mesh with a sun gear 64 integral wi h the driven shaft II. The gear 94 thereby forms the connection through which act'on oi the shaft II is begun.

Adjacent to the planet gear carrier 53 I provide a supporting disc 05 which terminates in a cylindrical flange 35. The flange 60 supports a substantially cylindrical sleeve 61 having a r ng gear 09 integral therewith. v A peripheral flange l extends outwardly from, the end of the leeve 1 and a circular flange 1I is'secured thereto by bolts 12. The circular flange 1I term nates in a The double gear I connected together. The larger diameter gear 81 is in constant mesh with the ring gear 59.

Three relativelyrotatable sun gears are provided in addition to' the sun gear 54 integral with the driven shaft I I. The first of these sun gears 89 is formed on the end of a sleeve 90 encircling the shaft II. A brake disc 9I extends outward'y from the sleeve 90 and is splined thereto to move in unison therewith. An ofiset a: mule disc 9| provides a space for a disc interconnecting means that will be later described in detail. The disc 9| terminates in a brake drum 99 engaged by a brake band 94 in a manner which will be later described.

A sun gear 95 is integrally secured to a sleeve 90 encircling the sleeve 90 to which is keyed the hub 91 of a brake druni disc 99 terminating in a brake drum I00. A brake band I0 l encircles the brake drum I00 and is operated in a manner which will be later described in detail. Thesun gear 95 is in constant mesh with the small diameter gear 95 of the double gear unit 85.

A' sun gear I02 is secured integrally to a sleeve I03 encircling the sleeve 95 which in turn is secured to the brake drum disc I04 terminating in the brake drum I05. A brake band I06 encircles means which is controlled by a disc I01 terminata ing in a brake drum I09 about which is pasring gear" which is oi a smaller diameter than the'ring gear 99. It will be seen that the ring gears 69 and 13 operate in unison as they are tioned'a brake band H0. The manner in which the interconnecting means which may be used to cause rotation of the sun gears 95 and 39 in unison will now be described.

With special reference to Figure 3 of the drawings. it will be noted that the driven shaft II is encircled by the sleeve 90. The sleeve 95 encircles the sleeve and is secured by a keyed or splined connection to the hub 91 of the brake drum disc 99. The offset portion 92 of the brake drum' disc 9! is 01 somewhat larger diameter than the hub 91 and provides a space in which three split rings disc I01 and separates the inner ring III from'an outer ring H5. The outer ring III is provided with hook ends H6 and H1 which are positioned to engage the ends of split collar II4. Movement of the disc 9| in one direction will tend to move one end II6 of the ring II5 against the end of the collar II4, while the movement of the disc 9| in the opposite direction will tend to move the hook end II1 of the ring II5 against the other end of the collar H4. The ends II9 of the ring II5 are cut on an angle to fit the corresponding angle of the lug I I2.

In operation the rings III and H5 act to provide a means of connecting the hub 91 with the offset portion 92 of the brake disc 9|. When the brake band IIII is in engagement with its brake drum I99, the disc I91 is held from rotation, and accordingly the lug H9 and the split collar II 4 are held from rotation. In such an instance the lug II2 on one end of the split ring III engages the lug I I9 due to the dragging action of the hub 91 thereagainst. However, as the hub 91 tends to rotate in a counter-clockwise direction, the forward end of the band in the rotation of the same engages the lug H9 and prevents the band III from wrapping tightly around the hub91. Simultaneously the disc 9| tends to rotate in aclockwise direction causing the hook end II6 of the outer ring H5 to engage the corresponding end of the split collar II4. Thereby the outer band H5 is prevented from expanding against the offset portion 92 of this disc.

When this disc I91 is released and is free to rotate with the remaining elements the pressure of the lug II9 against the lug II2 on the end of the band III is released. This permits the band to engage the hub 91 more firmly and brings the opposite lug II2 on the other end of the band against the inclined end 9 of the hook end H1 1 of the bandI I5. In other words, movement of the bands or rings in opposite direction will tend to expand the band II5 and contract the band I II so that the disc 9| and hub 91 will rotate in unison. Accordingly, when the brake band I I9 is loosened on the brake drum I99, the sun gears 99 and 95 will rotate in unison.

In some instances it is desirable that the sun.

rotate therewith. Splined to the sleeve I29 I provide the hub I2I of the clutch disc I22. The clutch disc I22 is provided with a friction facing I29 in each side thereof. One friction facing I29 is designed to engage the face of the brake drum disc 9|. The other friction facing I29 is designed to engage a ring I24 by means of which pressure may be applied. The ring I24 is parallel to the disc 9|, and maybe moved toward or away from the disc 9|, being splined or keyed to the inner surface of the brake drum 99. Movement of the ring I24 toward the disc 9| causes the clutch disc I22 to be squeezed between the ring I24 and the disc 9|, causing the disc I22 to rotate in unison with the disc 9|. Movement of the ring I24 away from the disc 9| relieves the pressure,.and permits independent rotation of these parts.

IA spring metal disc I26 encircles the hub I2I, and is held within the brake drum 99 by means of a split spring ring I21 which is held in place by an internal flange I29 within the drum 99. The

disc I26 is provided with a series of radially exshanks of double headed retaining pins I9I. The pins I9I are slidable in the slots I99 in a radial direction with respect to-the disc I26; and when in their outermost position engage in sockets I92 (formed integral with the ring I24. The pins I9I are held engaged in the sockets by means of a spring retaining ring I99 engaging the inner surface of these pins I9I. The pins I9I thus removably connect the ring I24 and the disc I29.

A sleeve I94 encircles the hub I2 I, and is longitudinally slidable with respect thereto.: A flange I95 is provided on one end of the sleeve I94, to engage interiorly of the disc I26. By means of a series of rings I96 which encircle the sleeve I94, a shifting sleeve I91 is secured to the sleeve I94. The shifting sleeve may rotate with respect to the sleeve I94, but moves longitudinally therewith. The means for longitudinally sliding this assembly in order to engage and disengage the clutch disc I22 will now be described in detail with special reference to Figure 6 of the drawings.

The entire transmission is encased within an outer casing I99. This casing I99 is formed In two parts'to be easily removable. One end plate I49 thereof terminates in a cylindrical flange I which is bolted by bolts I42 to the cylindrical casing I49 which encircles the transmission in spaced relation thereto. An end plate I44 forms the end of the casing I49; and a bearing I45 in the end plate I 44 supp rts the driven shaft I I.

A hydraulic cylinder I46 is secured adjacent th and plate I44 to a supporting spider I96 shown in Figures 1 and 2. A piston I41 within the cylinder I46 is secured by the piston rod I49 to a yoke I59, which moves'in a radial direction with respect to the shaft I I when actuated by the piston I41. The

- yoke I59 is pivotally connected to one end of a bell crank I5I; and the other end of this bell crank I5| is pivoted to the shifting sleeve I91. The Intermediate pivot I52 of the bell crank is connected by the link I59, which in turn, is pivotally connected at I 54 to the end plate I44 or to the spider I99.. Preferably, each of the bifurcated ends of the yoke I59 is connected to one of the bell cranks I5 I to equalize the strain.

From the foregoing description, it will be clear that as the piston I41 moves downwardly in the cylinder I46, the bell cranks I5I will be rotated in a clockwise direction as viewed in Figure 6, sliding the shifting sleeve I31 to the right, and disengaging the clutch. As the piston I41 moves upwardly in the cylinder I49, the shifting sleeve I91 will be moved to, the left, engaging the clutch plate by pressing the ring I 24 against the clutch disc I22 and creating increased friction between this disc I22 and the ring I24 and the brake drum disc 9| by means of the spring I25.

94, |9| and I96 are applied about their respective brake d ums 99, I99, and I95 is not of particular importance in the present invention. In order to illustrate the manner in which this may be accomplished, however, attention is directed to Fisure '7 of the drawings.

A cylinder I55 is secured to the spider I99 within the transmission housing. A piston I96 is provided within the cylinder I55, which is attached by the piston rod I51 to the arm I59 keyed tothe shaft I69, pivotally mounted on the spider I99 of the housing I99 in any suitable manner. A crank I6I forms a part of the shaft I69, which terminates in a crank shaft I62. The crankshaft I62 engages in a yoke I69, pivoted at m to the shoe I59 secured to one end of the brake band Y When the piston I59 lowers in the cylinder I55.

the arm I59 rotates the shaft I69, rotating the crank I9I, and pulling the brake band 94 in a clockwise direction, compressing or tightening the band 94 about its drum 93, and stopping rotation of this drum.

With special reference now to Figure 2 of the drawings, it will be noted that a cylinder I19 secured to the spider I38 containsa piston Ill which operates through the rod I12, arm I13,

shaft I14-supported by the spider I38, arm I15 and yoke I18 to tighten the band I9I about its drum I99. The brake band IN is adjustably dead ended by the adjusting stud I11. similarly, the cylinder I19 is fixed to the spider I38, and contains a piston I89 connected to a piston rod I8I. The rod I8I acts through the arm I82, shaft I85, and shoe I86 to tighten the band I96 about its drum I95. The band I98 encircles the drum I95 in a direction opposite to the direction of operation 'of the bands 99 and MI, and is dead ended by the adjustment stud I81.

A hydraulic cylinder I89 is secured to the fixed spider I39, and contains a piston I99. The piston I99 acts through a piston rod I9I pivotally connected to an arm I92, which arm is rotatable with a shaft I93 supported by the spider I38. A second arm I99 isrotatable with the shaft. I93 and engages the yoke I95 which is pivoted to the brake band shoe I96 011' one end of the brake band II9 encircling the brake drum I99. A spring I91 tends to hold the band II9 released, and the braking pressure is applied to the band by the cylinder and piston.

The various cylinders I99, I55, I19, I19, and I99 are operated hydraulically by a control device best illustrated in Figures 8, 9, 10, and 11 of the drawings. The cylinder I98 is controlled by a conduit pipe I99 best illustrated at the top of Figure 1 of the drawings which connects this cylinder to the outlet port 299 of the control B. The cylinder I55 is controlled by operation of a conduit pipe 29! leading to the outlet port 292 of the control B. The cylinder I19 is actuated by pressure through conduit 293 communicating with a port 299 in the control B. A cylinder I19 is controlled by fluid pressure through a conduit 295 leading to the port 296 of the control B. Pressure through any of these various conduits I99,

29I, 299, or 295 'actuatesthe various cylinders to which it is connected. The cylinder I89 is controlled by fluid pressure through a suitable conduit connected to the port 298 of the control B.

The control B is provided with a reservoir 291 which is connected by an inlet 299' through the passage 2I9 to the inlet of the hydraulic pump 2| I. The pump 2! I may be or any desired design arranged to force liquid under'pressure into a pump outlet 2I2 which is provided with a check valve 2I3 to prevent pressure from entering the pump from the discharge thereof. The check valve 2I3 is urged by a spring 2I4 into the outlet and the tension of the spring may be adjusted by shortening or lengthening the spring within A spring I95 extends between the yoke I93 sages 2I9, 229, and HI.

I83 supported by the spider I38, arm I84, yoke tures 242 in the cylinder driven by a motor driven shaft2l 8. p v

A passage 2 I8 communicates with the discharge passage 2 I2 when the check valve 2 I3 is open and this passage 2I2 leads toan inlet port 2 I 1 or a rothrough the control valve, to enter anyof the out-- let ports 299, 292, 294, 299,and 298. Return passages 229, and HI communicate with the reservoir291 so that as the valve 2I9 is rotated, certain of the ports 299, 292, 294, and 296 may be communicated with the. high pressure liquid, whereas others of the cylinders are connected by external grooves 222 to the various exhaust pas- Obviously when one of the cylinders I48, I55, I19, I19 .or I89 are con.- nected to the exhaust passages the brake bands controlled by oil pressurein these various cylinders are released through action of the springs, such as the spring -I or.by the similar springs I91, 223, or 224. The spring disc I26 acts to return the piston I41 in the cylinder I46.

Rotation of the rotatable valve element 2I9 is accomplished by the toothed rack 225 which is in mesh with the pinion 229 on the rotatable valve 2I9. A spring 221 tends to rotate the rotary valve 2I9 toward its starting position so that rotation of this valve tends to increase the tension of the spring. The rack 225, thus tends to rotate the valve 2I9 toward a low speed ratio position of the transmission at all times.

In order to provide a means of bypassing excess oil to prevent injury to the pump 2II, 1 provide a relief oil passage 239 with the oil inlet 2I9 to the pump 2II. A check valve 23I is urged by the spring 232 into closed position so 1 sage 2I9 of the pump 2| I. The plunger portion 289 of the check valve MI is cut away to permit oil to pass freely through the inlet passage 2I9 from the reservoir connection 299.

A second compensating pump 239 is connectedto the pump 2II to rotate therewith and is of considerably smaller size than the operating pump 2| I. The pump 299 is connected by an in let passage 295 to the reservoir 291 and the outlet of the pump 234 is connected to an outlet port 238 positioned near one end of a cylinder 281. The cylinder 231 accommodates the piston 239 to which is attached the rack 225. Thus as oil pres-' sure is forced by the pump 294 through the inlet port 235 or the cylinder 231 the rack 225 will be moved to the right as illustrated in Figure 9, rotating the pinion 226 in a clockwise direction and thus rotating the rotary .valve 2 I9 to control the transmission A. The cylinder 231 is provided with an adjacent smaller cylinder 249 which is parallel to the cylinder 231. A series of escape openings 24I extend through the wall of the smaller cylinder 249 and through aligned apermoves to the right as illustrated in Figure 9, a greater number of the openings 242 are exposed, for a purpose which will be described in detail.

In order to maintain somewhat of a balance between the speed of the engine and the output 01' the compensating pump 234,1 provide an escape valve 293 which is operated in conjunction I the threaded socket 2I5. The pump 2II may be 231. As the piston 239 with the foot throttle of the internal combustion engine with which the transmission is used. As the foot throttle is depressed, accelerating the engine, the valve 243 opens, to permit more of the liquid to escape through the escape passage 244 to the reservoir 201. The escape of the liquid through the valve 243 is not suflicient to prevent the building up of a pressure within the cylinder 231. The valve 243 serves to retard the movement of piston 239 to the right in accordance with the amount of depression on the foot accelerator. This allows the engine to run in each speed ratio at a higher rate of speed than when the accelerator is depressed lightly.

An elongated plu'nger 245 is slidably accommodated within the smaller cylinder 240, and is provided with rack teeth 246. A portion of the upper surface of the cylinder 240 is cut away, and a pinion 241 engages the teeth 246. The pinion 241 is mounted on the shaft 249 to rotate therewith; and this shaft 249 is rotatably mounted in a boss 250. The shaft 249 extends through the housing 25I of the control B, and may be rotated by any suitable operating handle. By operation of the handle, not shown, theshaft 249 is rotated, sliding the plunger to any point within limits in its cylinder 240.

Movement 'of the plunger 245 acts to control the gear ratio of the transmission by closing more or less of the openings 242 into the cylinder 231. The piston 239 will move to the right only until it uncovers a passage 242 not closed by the plunger 245. As soon as the piston 239 tends to move past this opening 242, the liquid under pressure within the cylinder 231 is exhausted therethrough until the piston again moves to the left sufficiently to virtually cover the openaperture 242. For

A yoke 265 is pivotally supported upon a stub shaft 266 and straddles the shaft 249 between the cams 263 and 264. A pin 261 on one arm of the yoke 265 engages the cam 264 and a second pin 269 on the other arm of the yoke 265 engages the other cam 263. The cams 263 and 264 'are so arranged that the yoke 265 is oscillated from one extreme position to the other as the plunger 245 moves to the left as seen in Figure 9. From the position which it occupies in this figure, oscillation of the yoke 265 rotates the stub shaft 246 which in turn oscillates the arm 210 to which is pivoted the operating lever 52. Thus, the lever 52 is urged downwardly when .the plunger 245 reaches a predetermined point in its movement manually engaging the pins 36 in the openings 39 in the gear carrier 33. The pumps 2 and 234 are driven by any suitable means, not illustrated in detail in the drawings.

Having now described the construction of the transmission and control means, I now desire to describe the operation of the device. Let us state for example, that the control lever on the operating shaft 249 is rotated to one extreme position,

' 245 is in this extreme position the cams 263 and 264 have oscillated the yoke 265 in a manner to urge the operating rod 52 downwardly into the I transmission. This action pivots the bell crank 50 sliding the actuating pins 4| .to the right as viewed in Figure 1 and thereby urging the pins example, with the setting of the plunger 245 illustrated in Figure 9 of the'drawings, the piston 239 will move to the right until the fourth apermm 242 from the left end of the series of the apertures is partially uncovered, as the first three apertures of the series are closed by the-plunger 245. When the piston 239 reaches this point,

however, additional pressure tends to exhaust through this fourth aperture 242, and sumcient pressure to force the piston 239 farther to the right cannot be built up. It will be noted, however, that any speed ratio 'lower than that for which the plunger 245 is set may be obtained.

In order to hold the transmission in one set position or another, rather than to remain in intermediate positions for any great length of time, I provide a ball 252 which is urged by a spring 253 into any of a series of detents 254. The detents 254 are in the rack 225, and tend to hold the rack in any one of a series of set positions.

A lever 255 is pivoted at 256 to the housing 25I, and a stop rod 251 is pivoted at 259 to the lever 255 to limit movement of the piston 299 in one direction, An arm 260 rotatable with lever 255 supports a cam follower ,26I which engages a cam 262 on the shaft 249. The earn 262 is so As best illustrated in Figures 9, 10, and 11 of the drawings, a pair of spaced cams 263 and 264 are provided on the shaft 249 for operating the control rod 52 for operating the locking pins 36.

36 into their respective openings '39 in the gear carrier 33 and locking the gear carrier 33 for rotation with the drive shaft I0. Furthermore, in this position the cam 262 has'released the cam follower 26I so that the piston 239 in the control cylinder 231 can move to the end of the cylinder.

The rack 225 in this position of the control extreme left hand 'has rotated the rotary valve 2I9 to a rotary poacts through the'arm I13, shaft I14, arm I15,

and yoke I16 to tighten the brake band IOI about itsdrum I00. 95. stationary. With the sun gear 95 held stationary, rotation of the drive shaft causes rotation of all of the gear carriers in unison as the gear carrier 33 is locked to the drive shaft by means of the pins 36. Power is then transmitted through the double gear unit to the ring gear 69 which operates in unison with the ring gear 13. Thus the rotation of the ring gear 13 is controlled by holding the sun gear stationary, and as the gear carriers supporting the double gears 6| rotate in unison with the drive shaft, a reverse rotation is transmitted from the gear 62 to the sun gear 64 on the driven shaft II.

In other words, 'as the sun gear 95 is held fixed and as the gear carriers and all of the planet gears rotate at the same speed, the double, gear units 85 revolve about the sun gear 95 which causes the ring gears 69 and 13 to rotate in a set relation thereto. The sun gear 64 on the driven shaft is revolved in a reverse directionfaster than it is carried forward by the transmission, acting to rotate the driven shaft II ina reverse direction.

By rotating the manual control shaft 249 slightly, -theplunger 245 is moved beyond the first set of apertures and closes off this first set This action holds-the sun gear of apertures. Simultaneously thepiston 220 and the pm 251 are moved to the right by the action of cam 202, rotating the rotary valve 2 II. when in the next position of the valve 2I9, the pressure from the pump 2 is returned to the reservoir 201. In this position of the valve 2I9, no

fluid under pressure is directed to the transmission, and the transmission merely idles about its driven shaft. This is neutral position of the transmission.

Further rotation' of the valve 2I9 causes the moved past the next successive opening 242,

which prevents the escape of liquid under pressure ,withln the cylinder 231 until the piston 239 moves farther to the right. This permits any speed ratio less than that at which the transmission is set to be obtained when desired; but limits the movement of the piston 239 to the right. In other words, when the plunger 245 is moved to set the transmission in intermediate 09 and I02 from rotation. The gear unit 05 is caused to revolve about the gear I02 producing a certain rotation of the ring gear 59, 13. Simultaneously, the double gear 0| is caused to revolve about the sun gear 09. This action transmits to the driven'gear 04 a speed ratio of 2.44 to 1 in the driven gear with respect to the drive shaft I0, in the transmission illustrated.

When the valve 2I9 is set to superintermediate position, as pressure is released from the cylinders' I19 and I55, no pressure is transmitted to the cylinder I39, actuating the piston I90. This action releases the brake band I I0 from its drum I09, acting in the manner previously described to interlock the sun gears 99 and 99. for rotation in unison. This interlockingaction produces a resulting rotation of the ring gear 69, 13 and of the double gear unit 0| which will drive the driven shaft 04 at a speed ratio of 2.18 to 1 with respect to the drive shaft in the particular transmission illustrated.

With the valve 2I9 set to intermediate position, fluid under pressure is transmitted to the cylinders I55 and I10, acting to hold the sun' gears 09 and 95 from rotation. The gear 85 of the double gear unit 95 is caused to revolve about the gear 95, producing a certain rotative speed of the ring gear unit 09, 13. At the same time, the gear 83 of the double gear unit Si is revolved about the sun gear 99, which will provide a resultant forward speed ratio in the driven gear gear, the piston 239 may move to the right until the transmission is in intermediate; but at this point an increase in pressure in the cylinder 231 will allow liquid to exhaust, so that the transmission will not move into high or overdrive.

This action is provided so that the engine may be used as a brake while going down grade with the vehicle.

As the piston 239 moves to the right a step at a time, the rotary valve 2I9 is rotated. Thus there is a definite position of the valve 2I9 for each gear ratio listed above.

When the valve 2I9 is in position for superlow, this valve 2I9 directs fluid to the cylinder I19, moving the piston I90 outwardly, and acting to tighten the brake band I09 upon the brake drum I05. This stops the sun gear I02 from rotation. The double gear 85 is then causedto revolve about the sun gear I02. By means of the double ring gear 69, 13, movement is transmitted to the double gear unit 6| which causes rotation of the sun gear 94 on the driven shaft II. The relative rotation of the gear units 85 and BI in 54 of 1.46 to 1 with respect to the drive shaft, in the particular transmission illustrated.

With the valve 2I9 set into overintermediate position, fluid is directed to the cylinder I19. This causes the brake band I 06 to be tightened about the drum I05. Through the previous two' speeds the brake band IIO has remained released from the drum I09. This action causes rotation of the sun gear I02 to be arrested, and causes the sun gears 89 and 95 to be interlocked to rotate in unison. The gear unit 85 is forced to When the valve 2I9 is set in position for high gear, the fluid under pressure to cylinder I40 is the transmission illustrated provides a forward I19. "I'his fluid moves the piston I to tighten the band 94 about the brake band drum 93. The sun gear 89 is then held stationary. The double gear unit 6| is then caused to rotate about the sun gear 89, causing thegear 92 of this unit to rotate the sun gear 64 on the driven shaft II at a speed ratio of 2.78 to 1 in the transmission illustrated, with respect to the drive shaft I0.

With the valve 2I9 set to overlow position, the cylinders I19 and I55 are both subjected to fluid pressure.- This acts to tighten both the brake bands 94 and I09 about their respective brake drums 93 and I05, arresting the sun gears ,to the cylinder I19.

now released, which engages the clutch disc I22 with the disc 9|, thereby causing sun gear 99 to rotate with the driven shaft. This action tends to stop rotation of the gear unit SI, and the entire transmissionrotatesas a unit, the driven shaft rotating at the same speed as the drive shaft.

When the valve 2I9 is set into position for overdrive, the fluid under pressure is transmitted This action tightens the band I09 about thedrum I05, arresting movement of the sun gear I02. 01 of the double gear unit to travel about the gear I02 at a predetermined rate. However, as the gear unit 5| cannot revolve about the sun gears 94 and 09, being locked to rotate in unison therewith, the gear carrier 23 is forced to travel faster than the other gear carrier, resulting in driving the driven shaft at a speed greater than the speed of the drive shaft, in a ratio of 1 to 1.33%; in the transmission illustrated.

When the valve 2I9 is set into position for superoverdrive, from cylinder I This causes the gear fluid under pressure is released "and transmitted to cylinder- I19, acting to hold thebrake drum I99' from rotation, and holding the sun gear 95 stationary.

- Much the same action as that described in. connection with overdrive then takes place.

The gear unit 6I is locked from rotation with respect to the driven gear 64 by the locking of the sun,

gear 89 to the driven shaft II. This necessitates the gear carrier 33 moving faster than the drive shaft, as the gear 99 of the gear unit 85 rotates about the fixed sun gear 95 at a predetermined rate of speed. The speed ratio between the driven shaft and the drive shaft in the transmake use of the compression of the motor as a brake while decelerating or travelling down a hill, the control illustrated is of advantage.

With special reference to Figure 12 of the drawings, a modified form of interlocking means will be described which may be used in the place of the previously described interlocking means best illustrated in Figure 3. In this construction the numeral 9i indicates, as in the other previously described construction, the brake drum disc connected to the sun gear 89, while the numeral 91 indicates the hub of the brake band disc-99 of the brake band I99. Interposed be tween the brake drum disc 9| and the disc 99 is the brake drum disc 215 which takes the place of the brake drum disc l91 previously described. The disc 215 may be considered to terminate in a brake drum I99 upon which the brake band II9 operates. Mounted upon the disc 215 I provide a lug 216 and a substantially Z shaped projection 211. These projections extend into the cylindrical space between the hub 91 and the offset portion 92 of the brake drum disc M.

A split ring 219 encircles the hub 91 and has a tendency to wrap around this drum. The end of the ring 219 is provided with an inclined race 289 upon which may operate a ball or roller MI. The roller 28I is urged by a plunger resiliently actuated by a spring 283 recessed in a lug 284 on the outer surface of the ring 219. Obviously when the hub 91 is rotating in a counterclockwise direction and the brake drum disc M is travelling in a clockwise direction, the roller 28I will be urged by the plunger 282' between the inclined portion 289 of the ring 219 and the inner surface of the offset portion 92 tending to cause the hub 91 and the brake drum disc 9| to rotate in unison.

In order to prevent operation of these two elements in unison a rocker am 2 85 is pivoted at 286 to the end of the ring 219. Opposite the end bearing the incline 299 a pivoted finger 281 is pivoted at 299 to the rocker arm 285 and extends between the substantially Z-shaped projection 211 and the surface of the portion 92 In one pivoted position of the-rocker arm 295 the finger 281 engages against the ball or rocker 28I urging the same ,down the incline and preventing the rocker from locking these two elements from relative rotation.

In order to operate the rocker arm 285 it is only necessary to stop rotation of the brake drum disc 215 by engaging the brake band I9I about the brake drum I99. When the disc 215 is held from rotation,,one end of the l-shaped projection 211 engages an end of the rocker arm 285 sliding the finger 231 against the roller 2" and releasing the same from engagement with the inner surface of the offset portion 92, thereby permitting independent rotation of I the hub 91 and the brake drum disc 9|. As soon as the band H9 is released, however, a pressure against the rocker arm 285'is released, allowing the finger 281 to slide back into the position illustrated in Figure 12 and permitting the plunger 292 to urge the roller 29I into interlocking position as shown.

In Figure 13 of the drawings I disclose a typical installation for my transmission which shows the manner in which the transmission may be conveniently used on a tank or tractor C. Figure .13 discloses the end of a power unit, such as an internal combustion engine showing the fly wheel 299 and the drive shaft 29L A double bevel gear unit comprising a. bevel gear 292 and a bevel gear 293 is rotatably mounted upon the drive shaft 29I and may be shifted longitudinally of the drive shaft by any suitable shifting mechanism 294. The bevel gear 292 is designed to. engage a 00- operating bevel gear 295 in one position of the bevel gear unit in order to drive the power takeoff pulley 296. In the other position of the bevel gear unit, the bevel gear 293 engages a bevel gear 291 and is rotatably mounted upon a drive shaft not shown in detail in the drawings. A transmission A is mounted on each side of the center on each of the transverse drive shafts, each designed to deliver power to a driven shaft 299 upon which is mounted a drive pinion 399. Each pinion 399 engages a gear 39I which is connected by a sleeve 392 to a chain sprocket 393 or any other suitable connection to the wheel or treads of the tractor or tank.

A control B is provided for each transmission which is o perated in the manner previously described by an operating lever 394. By operation of the levers 394 each of the transmissions A may be individually operated and may supply the same speed ratio to both of the drive sprockets 393 or may, if desired, provide the same speed to both of these sprockets. Thus, the drive sprockets 393 may be actuated at the same speed or at any individual speeds.

In Figure 14 of the drawings I disclose one form of control device operated by the control rod 394. The control rod 394 is keyed to a planet gear carrier 395 supporting a pair of planet gears 3,96 which mesh with gear teeth 391 on the end of the rotary control valve 399. The pressure from the pump 2I I is supplied to the rotary valve 399 through the intake port 3I9 and maydeliver fluid under pressure to any of the cylinders 3,

j 3l2, "3,3", or 35. The cylinders 3, III, 3,

3I4, and 3I5 are equipped with pistons similar to those shown in Figure 15 and which will be later described. In this type of construction, the valve unit is directly connected to the cylinders operating the various brake bands eliminating the need for pipes ,or conduits. The cylinders 3| I, 3l2, III, 3 and MS may be spaced the'same as the brake bands operated thereby, thus eliminating all need of conduits or piping. Such a construction is of particular value when the transmission is used on tanks and the like.

If the control of Figure 14 were to be used with the transmission and arranged as In Figures 1 and 2 of the drawings, the cylinders M I, 9I2, 3I3, 5I4, and 3I5 would form exhaust ports. The exhaust port m is then connected to th cylinder I19 in the transmission to operate the piston Ill. The port 3I2 i connected to-the cylinder I19 to operate the piston III. The port I is connected to the cylinder I55 to operate the piston I56. The port 3 l 5 is connected to the cylinder I46 to operate the piston I41. The port 313 is connected to the cylinder I39 to operate the piston I96. It will be obvious that by pivoting the control lever 364, liquid may be distributed to any of the. desired control units for operating the transmission A to provide any desired speed ratio. In Figure of the drawings I disclose a slightly modified form of brake applying means by which the brake drums 93, I66, I65, and I69 maybeheld from rotation. This figure does notv disclose a complete cross-section through the transmission as it will be understood that any of the drums may be held from rotation by this means. As shown in this figure the brake drum 316, which may be any of the brake drums previously described, may be engaged by a pair of oppositely disposed brake shoes 3l1 equipped with a brake bandsurface 3l9. The shoes 3I1,are pivotall-y supported at 326 by a U-shaped support 32l. A spring 322 tends to hold the brake shoes 3" spaced from the drum 3I6.- A lever 323 pivoted at 324 to the fixed bracket 325 is pivoted at 326 to the brake shoes 3| 1. Movement of the levers 323 is controlled by pistons321 within the cylinders 329. When hydraulic pressure is introduced through the conduit 336, the pistons 321 operate the levers 323 to apply the brakes to the brake drum 3I6.

Figures 17, 18, and 19 of the-drawings disclose modified forms of construction showing difierent manners in which the ringgears may be connected to the double gear'units. In these figures the double gear units 6|, including gears 62 and 63 are shown connected with an integral rin gear. In Figure 17 the integral ring gears 33! and 332 are shown in mesh with the gears 62 and 81, re--.

spectively. In Figure 18 the ring 333 is connected to ring gear 334. Ring gear 333 is in mesh with planet gear 62 of the double gear unit 6 I, and the ring gear 334 is in mesh with planet gear 86 of the double gear unit 85. In Figure 19 the ring gear 335 is connected to the ring gear 336, and these ring gears are shown connecting the gears 63 and 96. Thus these various combinations of ring gear structure may be used in placeof the connected ring gears 69 and 13 if it is desired to provide various speed ratios -for different constructions.

andsupports a sun gear 362 engageable with the gear 35L A brake drum 363 is keyed to the sleeve 36l and is operated by a suitable brake band. A sleeve 364 encircles the sleeve 3!, and bears-a sun gear 365 which engages the gear 366 of the double gear unit 346. A brake drum 366 is connected to the sleeve 364, operated by a suitable brake band. A sleeve 361 encircles the sleeve 364, and bears the sun gear 369 which engages the gear 355 of the double gear unit 346. A brake drum 316 is keyed to the sleeve 361, which may be engaged by a suitable brake band as described in the transmission A.

The gear carrier discs 341 and 349 may be made to rotate with the drive shaft 331. A clutch gear 311, best illustrated in Figure 21 of the.

drawings, is slidable upon theend of the driven shaft 359, into or out of engagement with a complementary clutch gear 312 on the gear carrier 341. Pins 313 engage the gear 3" to slide the same. The pins 313 are moved by radially extending pins 314, movement of which is controlled by a sliding ring device 315 similar to that previously described.

' 365 for rotation in unison, I provide on the hub 316 of the brake drum disc 311 of the brake drum started. The hollow cylindrical casing 342 is connected to the end plate 346, terminating in an end plate 343 which acts as a planet gear carrier.

Bearing shafts 344 extend between the end plate 343 and th gear carrier plate 345 bolted thereto; and double gear units 346 are mounted thereupon, being supported by needle bearings. A

second pair of gear carrying discs 341 and 349,

bolted to rotate in unison, support stud shafts 356 which support the double gear unit 351, which 366 a slidable gear 319 which is splined or keyed to the hub 316. This gear 319 is a clutch gear similar to the clutch gear 312 illustrated in Figure 21 of the drawings. On the disc 386 of the brake drum 363 I provide a complementary gear 38L A flange 382 extends outwardly from an edge of the gear 319 which is engaged by the bifurcated end 383 of the gear shifting bracket 384. By movement of the shifting bracket 384 the position of the gear 319 may be moved from engaging position in which the gear 319 engages the gear 38 l, causing rotation of the sun gears 362 and 365 in unison.

The shifting bracket 384 is. slidably mounted "on a shaft 385 supported by the enclosing housing 386 of the transmission D. p The shaft 385 slides in bearings 381 and 339 on the housing 386.

A bracket 396 is mounted on the shaft 335 to slidetherewith. A light spring 39! is mounted between the bracket 396 and the end plate 392 o the housing 386.

A piston rod 393 is secured to the bracket 396, and is slidable through an opening in the bracket. A piston 394 is mounted on the piston rod 393. A spring, which is substantially twice the strength of thespring 391, is indicated at 395 encircling the piston rod 393 between the piston 394 and the bracket. The piston 394 is mounted within acylinder 396, which is connected by a suitable conduit 391 to the control unit B. The conduit 391 may be connected to the port 266 of the control unit. I y

When desired, fiuid pressure enters the cylin- (her 396, forcing the piston 394 to the right as seen in Figure 26. Pressure upon the spring 395 moves the bracket 396 to the right, moving the rod or shaft 285, to the right as seen in Figure 20. This causes engagement of the gears 319 and 38l,

causing the sun gears 362 and 365 to rotate in unison.

The clutch gears 312 and 319 are provided with teeth 399 which are provided with bevelled en-' gaging edges 466 to lessen the shock of engagement. The form of these teeth is best illustrated in Figure 21 of the drawings. In general, the transmission D operates in a manner identical to the manner of operation of the transmissionv A, with the changes described.

From the foregoing description of my transmission A, it will be apparent that when it is desired to reverse the transmission, the lock band H is in engagement with the drum I09 and the cooperating elements as heretofore set forth will function to reverse the transmission.

With this transmission, I am able to secure nine forward speeds which may be described in a simple manner as follows:

What I term as superlow" is obtained by causingthe brake band I06 to engage the drum I05, which is the first speed.

The second speed, which I term low is obtained by locking the band 94 to the drum 03.

The third speed, which I term overlow" is obtained by locking the bands I06 and 84.

The fourth speed, which I term "superintermediate is obtained by locking the band H0 to the drum I09.

The fifth speed, which I term intermediate is obtained by locking the bands WI and 9d.

The sixth speed, which I term overintermediate" is obtained by locking the band I08 and the band H0.

The seventh speed, which I term "high is obtained by locking the clutch I22.

The eighth speed, which I term "overdrive" is obtained by locking the band I06 and the clutch The ninth speed, which I'term "superoverdrive is obtained by locking the band I0! and the clutch I22.

All of these speed changes are obtained in my transmission A without the disengagement of any of the intermeshing gears. When the transmission is operated by hand control, the different clutch bands, such as I06, IBI, H0, 08, and the clutch I22, must be released by operating the hand control and selecting the diflerent speeds. However, by the hydraulic control means which I have described heretofore, as the master controller B, in the operation of my transmission A, if the torque between the driving shaft I0 and the driven shaft I I becomes too great for the applied power on the drive shaft N, then the control B operates automatically to release brake bands and clutch means and to apply the proper brake band means so as to select the proper gear ratio between the driving member I0 and the driven member II. The plunger 65 and the piston 239 are adapted to actuate to rotate the rotatable planet gear carriers, means connecting valve 2I9, which in turn rotates to a definite position for the gear ratio required. In this manner, my transmission A operates automatically when controlled by the hydraulic master control B.

Thus it will be apparent that I have provided an automatically operating transmission to automatically select the proper gear ratio between the driving element or drive shaft of the motor driving the transmission, and the driven member which is adapted to operate the motor vehicle or tractor or device being driven.

When the transmissions are used in pairs, as illustrated in Figure 13, and applied to a tractor or a fiighting tank, such as is used in war, it may be desirable to operate the control members B of the respective transmissions by hand, and thus provide maneuverability to the tank by retarding the action of one transmission while speeding up the action of the other transmission, and vice versa, to operate the tank in any desired direction quickly and with the power necessary to carry the tank in the direction and at the speed desired.

In accordance with the patent statutes, I have described the principles of construction and operation of my transmission; and while I have endeavored to set forth the best embodiments thereof, I desire to have it understood that these are only illustrative of a means of carrying out myinvention, and that obvious changes may be made within the scope of the following claims without departing from the spirit of my invention.

I claim:

i. In a transmission, a drive shaft, a driven shaft coaxial therewith, a pair of epicyclic gear systems connecting said shafts comprising three relatively rotatable sun gears coaxialwith, and rotatable with respect to, said shafts, a pair of said carriers to rotate in unison, planet gear means on one of said carriers engaging one of said sun gears, second planet gears on the'other of said carriers engaging a second of said sun gears, ring gears of relatively different diameters connected together and engaging said first and second planet gear means, pinion means rotatable with said first named planet gears engaging the third of said sun gears, means connecting said second planet gears to said driven shaft to rotate said driven shaft, and means for holding said one sun gear stationary.

2. In a transmission, a drive shaft, a coaxial driven shaft, three relatively rotatable sun gears rotatable with respect to and coaxial with said shafts, planet gear means engaging one of said sun gears, a ring gear engaging said planet gear means, a planet gear support, means connecting said support to said drive shaft to rotate there with, second planet gears relatively larger than said first named planet gears engaging a second said sun gear, a second ring gear relatively larger than said first named ring gear engaging said second planet gears, said ring gears connected to rotate in unison, a second planet gear support, disengageable means connecting said second support to said drive shaft to rotate therewith, gear means rotatable with said first named planet gear means engaging the third of said sun gears, and gear means connecting said second planet gears to said driven shaft to rotate the same.

3. In a transmission, a drive shaft, a coaxial driven shaft, three relatively rotatable sun gears rotatable with respect to, and coaxial with, said shafts, planet gear means. engaging one of said sun gears, planet gear supporting means connected to, and rotatable together with, said drive shaft, ring gear means engaging said planet gear means coaxial with, and rotatable with respect to, said shafts, a second ring gear secured to, and rotatable with, said first named ring gear, second planet gear means interposed between and engaging said second ring gear and the second said sun gear, a second planet gear support relatively rotatable with said shafts, overrunning clutch means between said drive shaft and said second gear support to rotate said second support at least as fast as said drive shaft, but holding said second support free to rotate faster than said drive shaft, gear means rotatable with said first named planet gear means and engaging the third of said sun gears, and cooperable gear means connecting said second planet gears to said driven shaft.

4. In a transmission, a drive shaft, a coaxial driven shaft, three relatively rotatable sun gears coaxial with, and rotatable with respect to, said shafts, planet gear means engaging one of said sun gears, a ring gear engaging said planet gear means rotatable upon, and coaxial with, said shafts, a planet; gear support, means connecting said support to said drive shaft to rotate there with, a second ringgear larger in diameter than i said first named ring gear connected thereto and coaxial with said shafts, second planet gear means between and connecting said second ring gear and'the second said sun gear, pinion means coaxial and rotatable in unison with said first named planet gear means engaging the third said sun'gear, overrunning clutch means between said second gear support and saiddrive shaft, and selective means for holding'both said run gears stationary.

5. A transmission including a driving element, a driven element. a series of gear unitsinterposed between said driving and driven elements, a gear carrier, each gear unit including a pair of sun gearscoaxial with; said gear carrier, a coaccordance with the torque exerted against said driven element from said driving element.

6. In a transmission. a drive shaft, a coaxial driven shaft. three relatively rotatable sun gears second planet gear means, gear means on said driven shaft engaging said pinion means, means for locking said one sun gear stationary, and clutch' means. selectively locking said other sun gear from rotation relative to said driven shaft.

8. In a transmission, a drive shaft, acoaxial driven shaft, three relatively rotatable sun gears rotatable with respect to, and coaxial with 'said shafts, planet-gear means engaging one of said sun gears, planet gears supporting means connected to, and rotatable together with, said drive shaft, ring gear means engaging said planet gear means coaxial with, and rotatable with respect to, said shaft, a second ring gear secured to, androtatable with, said first ring gear, a second planet gear means interposed between, and engaging said second ring gear and a second of said sun gears, a second planet gear support rotatable relative to said shafts, overrunning' clutch means between said drive shaft and said second planet gear support to drive said second support at a speed equal to or greater than said drive shaft, pinion means rotatable in unison with said first named planet gear means engaging the third of said sun'gears, brake means secured for rotation with each 'of said sun gears, means cooperable with said brake means to selectively hold any of said sun gears from rotation, pinion means coaxial with and rotatable with said second planet gear means, and gear means on said driven shaft engaging said pinion means.

9. In a transmission, a drive shaft, a coaxial driven shaft, three relatively rotatable sun gears rotatable with respect to, and coaxial with'. said shaft, planet gear means engaging one of said sun gears, a first ring gear concentric with said' shafts engaging said planet gear means, a second ring gear secured to said first ring gear, a second planet gear means interposed between. and meshing with, said second ring gear and the second of said sun gears, a second gear support for said secondplanet gear means, an overrunning clutch between said second gear support and said driveshaft to rotate said second gear support in unison with said drive shaft. pinion means coaxial with, and rotatable'with, said secselectively interlocking said driven shaft and the second of said sun gears. 1

'7. In a transmission, a drive shaft,a coaxial rotatable with respect to. said shaft, a double ring ear comprising a first and second ring gear connected for rotation together, a first planet gear means between, and meshing with one of said sun gears and said first ring gear. a second planet gear means between and meshing with the other of said sun gears and said second ring gear, a first planet gear supporting means connected to and rotating with said drive shaft. a second planet gear supporting means, pinion means concentric with and rotatable with said second planet gear means, gear means on said driven shaft engaging said pinion means, pinion means coaxial with and rotatable with said first planet gear means, said last named pinion means engaging the third of said. sun gears, brake means connected to each of sa d sun gears,

driven shaft, three relatively rotatable sun gears coaxial with, and rotatable with respect to, said shafts, a doublering gear rotatable with respect to said shafts, said double ring gear comprising a first and second ring gear connected for rotation together, a first planet gear means between, and meshing with, one of said sun gears and said first ring gear, a second planet gear means between, and meshing with, the other ofsaid sun gears and said second ring gear, a first planet gear supporting means connected to, and rotating with, 'said driven shaft, a second planet gear supporting means, and overrunning clutch interposed between said second supporting means and said drive shaft, and free to rotate faster, pinion means coaxial and rotatable with said first planet gear means, engaging the third said sun gear,

pinion means coaxial and rotatable with said means cooperable with said brake means to stop either of said sun gears from rotation, clutch means interposed between said driven shafts and one ,of said sun gears to causerotation of said one sun gear together with said driven shaft, and

' meansse'lectively connecting said second planet rotation with said drive shaft, planet gears rotatably supported by said planet gear carrier en gageable with one of said sun gears, a second set of planet gears coaxial with, and rotatable with, a second of said sun gears, a second planet gear carrierrelatively rotatable with respect to said planet gear carrier relatively rotatable with respect to said shafts, a third set of planet gears of different diameter from said first named planet gears on said second carrier engageable with the third of said sun gears, a first and second ring gear of unequal diameters connected third sun gear stationary, fourth means for holding said third sun gear stationary, fourth planet gears coaxial with, and rotatable with, said third planet gears, gear means on said driven shaft engaging said fourth planet gears, and means connecting said second planet gear carrier to said drive shaft for rotating said second gear carrier therewith. I

11. In a transmission, a drive shaft, a driven shaft coaxial therewith, a pair of epicyclic gear systems connecting said shafts comprising three relatively rotatable sun gears coaxial with, and rotatable with respect to, said shafts, a pair of rotatable planet gear carriers, planet gear means on one of said carriers engaging one of said sun gears, second planet gear means no the other of said carriers engaging the second of said sun gears, ring gears of relatively different diameters connected together and engaging said first and second planet gear means, pinion means coaxial with said first planet gear means and said second planet gear means, thethirdof said sun gears engaging one of said pinion means, gear means on said driven shaft engageable with the other of said pinion means, and means for hold ing said first sun gear stationary.

12. In a transmission, a drive shaft,.a driven shaft, a planet gear carrier connected to said drive shaft for rotation thereby, a ring gear rotatable concentrically with said gear carrier, a pair of sun gears coaxial with said ring gear, planet gear means comprising a double gear unit comprising two gears connected for rotation in unison, said planet gear means being supported by' said gear carrier,'a second ring gear connected to said first named ring gear for rotation therewith, a pair of sun gears coaxial with said second ring gear, one of said last named sun gears being mounted on said driven shaft, a second gear carrier rotatable with respect to and coaxial with, said second ring gear, and second planet gear" means arried by said second gear carrier, said second planet gear means comprising a pair of gears connected for rotation in unison, one of said gears of said last named pair engaging said second ring gear and one of saidlast named sun gears, and the other gear of said last named pair engaging the other of said last named sun gears.

13. In a transmission, a drive shaft, a planet gear carrier connected to said drive shaft for rotation thereby, a first pair of sun gears coaxial with said planet gear carrier, a first ring gear coaxial with said 'sun gears, first planetgear means rotatably mounted on said gear carrier, said planet gearmeans including a pair of planet gears connected for rotation in unison, one of said planet gears engaging said first ring gear and one of said first sun gears, and the other of said planet gears engaging the other sun gear of said pair; a second ring gear connected to said first ring gear, a second pair of sun gears coaxial second pair is secured, and means connectin said second gear carrier to said drive shaft in a manner to insure the rotation of said second gear carrier at the same rate of speedor at a greater rate of speed than said drive shaft.

14. In atransmission, avdrive shaft, a first planet gear carrier connected to said drive shaft for rotation thereby, a first pair of sun gears coaxial with said planet gear carrier,- a first ring gear coaxial with said first planet gear carrier, 9. first planet gear means carried by said first planet gear carrier comprising a pair of gears connected for rotation in unison; one of the gears of said pair engaging said first ringgear and one of said sun gears, and the other of the gears of said pair engaging the other of said sun gears; a second ring gear connected to said first ring gear for rotation therewith, a second pair of sun gears coaxial with said second ring gear, a second planet gear carrier coaxial with said second ring gear, a second set of planet gear means carried by said second planet gear carrier, said second planet gear means comprising a pair of gears, one of which meshes with said second ring and one of I said sun gears of said second pair, and the other which meshes with the other of said sun gears of said second pair, a driven shaft driven by one of said sun gears of said second pair, and brake means for holding any of the remaining sun gears from rotation 15. In a transmission, a drive shaft, a first planet gear carrier connected to said drive shaft for rotation thereby, the first pair of sun gears coaxial with said planet gear carrier, a first ring gear coaxial with said first planet gear carrier, a first planet gear means carried by said first planet gear carrier comprising a pair of gears connected for rotation in unison, one of said gears of said pair engaging said first'ring gear and one of said sun gears, the other of the gears of said pair engaging the other of said sun gears, a second ring gear connected to said first ring'gear for rotation therewith, a second sun gear coaxial with said second ring gear, a second planet gear carrier coaxial with said second ring gear, .a second set of planet gear means carried by said second planet gear carrier, said second planet gear means comprising a pair of gears, one of which meshes with said second ring gear and said second sun gear, driven shaft and gear means connected to said driven shaft to rotate the same, meshing with the other of said ears of said second pair, brake means for holding any of the sun gears from rotation, and means connecting one of said sun gears with said driven shaft to rotate therewith.

16. In a transmission, a drive shaft, a first planet gear carrier connected to said drive shaft with said second ring gear, a second planet gear carrier coaxial with said second ring gear, a second planet gear means mounted on said second planet gear carrier, said second planet gear means comprising a pair of gears connected for rotation in unison, one of said last named pair of gears engaging said second ring gear and one of said sun gears of said second pair, the other gear of said last named pair of gears engaging the other of said sun gears of said second pair, a driven shaft to which one of saidsun gears of said for rotation thereby, a first pair of sun gears coaxial with said planet gear carrier, a first planet gear means carried by said first planet gear carrier comprising a pair of gears connected for rotation in unison, one of the gears of said pair engaging said first ring gear and one of said sun gears, the other of the gears of said pair engaging the other of said sun gears, a second ring gear connected to said first ring gear for rotation therewith, a second sun gear coaxial with said second ring gear, a second planet gear carrier coaxial with said second ring gear, a

' second set of planet gear means carried by said second planet gear carrier, said second planet gear means comprising a pair of gears, one of which meshes with said second ring gear and with one of said sun gears of said second pair, a 

